摘要
供水管网的铁释放问题近年来日益受到关注.影响供水管网铁释放的因素众多,本研究选取了pH、溶解氧(DO)、碱度(Alk)、硬度、氯离子(Cl^-)、硫酸根(SO_4^(2-))、温度(T)和水力停留时间(HRT)这8个影响因素,利用逐步回归和偏相关分析,建立了铁释放的非线性幂指数模型,并用标准化回归系数和偏相关系数比较了这些因素的相对重要性.结果表明,铁释放模型拟合效果良好;用标准化回归系数衡量影响因素相对重要性时,SO_4^(2-)、HRT、Cl^-和T是相对重要的因素,相对重要性排序为SO_4^(2-)≈HRT>Cl^->T;用偏相关系数衡量时,HRT、SO_4^(2-)、Alk、Cl^-和T是相对重要的因素,排序为HRT>SO_4^(2-)>Alk>Cl^->T.综合两种系数的分析结果,HRT、SO_4^(2-)和Cl^-是本研究条件下相对重要的因素,T和Alk的相对重要性视实际情况变动.
Iron release in drinking water distribution systems （DWDSs） has attracted significant attention in recent years. There are many factors influencing iron release in DWDSs. In this study, we select pH, dissolved oxygen （DO）, alkalinity （Alk）, hardness, chloride （Cl - ）, sulfate （SO2 -4 ）, temperature （T）, and hydraulic retention time （HRT） as factors to investigate. Stepwise regression and partial correlation analysis are used as methods for establishing nonlinear power exponent iron release models and determining the relative importance of these factors by comparing standardized regression coefficients and partial correlation coefficients. The results show that the iron release models fit well. The important factors are SO2 -4 , HRT, Cl - , and T, and the relative importance of the effect of the factors on iron release is SO2 -4 ≈HRT 〉 Cl - 〉 T, when measured by standardized regression coefficients; whereas, the important factors are HRT, SO2 -4 , Alk, Cl - , and T, and the order of importance is HRT 〉 SO2 -4 〉 Alk 〉 Cl - 〉 T, when measured by partial correlation coefficients. Combining these two results, we conclude HRT, SO2 -4 , and Cl - are the most important factors affecting iron release in pipes for the conditions in this study. The relative importance of T and Alk changes depending on the actual situation.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2017年第12期5090-5096,共7页
Environmental Science
基金
国家自然科学基金项目(51378493
51678558)
关键词
供水管网
铁释放
逐步回归
标准化回归系数
偏相关系数
drinking water distribution system
iron release
stepwise regression
standardized regression coefficient
partial correlation coefficient
